PATHOLOGY 



ders of the connective tissue ground sub- 

 stance and related structures. In the diseases 

 described here, the first and most important 

 changes are considered to be located in the 

 capillary basement membranes. According to 

 Gersh and Catchpole (1949) the latter are 

 condensations of the ground substance. 



The changes of the basement membranes 

 probably include a precipitation of a foreign 

 protein-containing substance, such as amy- 

 loid, and perhaps also a metabolic change, 

 such as a depolymerization, of the muco- 

 polysaccharides pre-existing in the basement 

 membrane. It may be presumed that a 

 change in permeability is evoked simultane- 

 ously with the thickening of the basement 

 membrane which may explain the apparently 

 controversial observations of a decrease in 

 filtration fraction and proteinuria in the 

 same patient (Bergstrand and Bucht, 19o9b; 

 Sitte, 1959). 



Important differences exist, however, 

 between the diseases associated wdth a ne- 

 phrotic syndrome. In lipide nephrosis and fa- 

 milial nephrosis the epithelial cells are se- 

 verely changed whereas little or no damage 

 is seen in the endothelium. In renal amyloi- 

 dosis both kinds of cells are damaged and in 

 glomerulosis the lesions are mainly located in 

 the endothelial cells. Furthermore, in the 

 cases of lipide and familial nephrosis, the 

 glomerular fi.ltration seems to have been nor- 

 mal. In amyloidosis and glomerulosis a de- 

 crease in filtration fraction was observed in 

 most cases. 



It is interesting to note that in glomerulo- 

 nephritis the main changes are also located 

 in the capillary basement membranes and 

 the endothelial cells. No definite conclusions 

 concerning eventual relationships between 

 the latter disease and those described above 

 should be drawn from this fact at the pres- 

 ent moment, however. 



Shock Kidney 



Electron microscopic investigations of the 

 renal changes in acute anuria (post-opera- 

 tive shock) have been published by Dalgaard 



05// 



Fig. 6. Diabetic glomerulosclerosis. Capillary- 

 basement membrane without apparent structure 

 but about three times thicker than normal and 

 with a thin band (B) of foreign material close to 

 the endothelial cell membrane (End). 



(1958a; 1959) and Putois (1959). There were 

 no glomerular lesions but severe damage to 

 the epithelial cells in the proximal and distal 

 convoluted tubules. The brush border w^as 

 partially or completely destroyed and in the 

 cytoplasm large vacuoles, severely damaged 

 mitochondria and "macrobodies" were ob- 

 served. The basal infoldings of the cell mem- 

 branes w^ere decreased in height or com- 

 pletely absent. In many cells these changes 

 had developed into complete necrosis with 

 destruction of most cell organelles. No re- 

 generation phenomena were observed. 



Experimental Tubular Changes 



Engfelt et al. (1957) have studied the in- 

 fluence of parathyroid hormone on the kid- 

 neys in rats. Electron microscopy, which has 

 been reported in more detail by Rhodin 

 (1958), showed an accumulation of very 



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